 /*******************************************************************************
  * Copyright (c) 2000, 2005 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/

 package org.eclipse.ui.actions;

 import org.eclipse.jface.action.Action;
 import org.eclipse.jface.action.ActionContributionItem;
 import org.eclipse.jface.action.IContributionItem;
 import org.eclipse.jface.action.IMenuCreator;
 import org.eclipse.jface.action.MenuManager;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.Menu;
 import org.eclipse.ui.ISharedImages;
 import org.eclipse.ui.IWorkbenchWindow;
 import org.eclipse.ui.internal.PerspectiveTracker;
 import org.eclipse.ui.internal.WorkbenchMessages;

 /**
  * Action which, when run, will open the new wizard dialog.
  * In addition, it has a drop-down showing the new wizard shortcuts
  * associated with the current perspective.
  * <p>
  * This class may be instantiated; it is not intended to be subclassed.
  * </p>
  *
  * @since 3.1
  */
 public class NewWizardDropDownAction extends Action implements
         ActionFactory.IWorkbenchAction {

     /**
      * The workbench window; or <code>null</code> if this
      * action has been <code>dispose</code>d.
      */
     private IWorkbenchWindow workbenchWindow;
     
     /**
      * Tracks perspective activation, to update this action's
      * enabled state.
      */
     private PerspectiveTracker tracker;

     private ActionFactory.IWorkbenchAction showDlgAction;

     private IContributionItem newWizardMenu;
     
     private IMenuCreator menuCreator = new IMenuCreator() {

         private MenuManager dropDownMenuMgr;

         /**
          * Creates the menu manager for the drop-down.
          */
         private void createDropDownMenuMgr() {
             if (dropDownMenuMgr == null) {
                 dropDownMenuMgr = new MenuManager();
                 dropDownMenuMgr.add(newWizardMenu);
             }
         }

         /* (non-Javadoc)
          * @see org.eclipse.jface.action.IMenuCreator#getMenu(org.eclipse.swt.widgets.Control)
          */
         public Menu getMenu(Control parent) {
             createDropDownMenuMgr();
             return dropDownMenuMgr.createContextMenu(parent);
         }

         /* (non-Javadoc)
          * @see org.eclipse.jface.action.IMenuCreator#getMenu(org.eclipse.swt.widgets.Menu)
          */
         public Menu getMenu(Menu parent) {
             createDropDownMenuMgr();
             Menu menu = new Menu(parent);
             IContributionItem[] items = dropDownMenuMgr.getItems();
             for (int i = 0; i < items.length; i++) {
                 IContributionItem item = items[i];
                 IContributionItem newItem = item;
                 if (item instanceof ActionContributionItem) {
                     newItem = new ActionContributionItem(
                             ((ActionContributionItem) item).getAction());
                 }
                 newItem.fill(menu, -1);
             }
             return menu;
         }

         /* (non-Javadoc)
          * @see org.eclipse.jface.action.IMenuCreator#dispose()
          */
         public void dispose() {
             if (dropDownMenuMgr != null) {
                 dropDownMenuMgr.dispose();
                 dropDownMenuMgr = null;
             }
         }
     };

     /**
      * Create a new <code>NewWizardDropDownAction</code>, with the default
      * action for opening the new wizard dialog, and the default contribution item
      * for populating the drop-down menu.
      *
      * @param window the window in which this action appears
      */
     public NewWizardDropDownAction(IWorkbenchWindow window) {
         this(window, ActionFactory.NEW.create(window), ContributionItemFactory.NEW_WIZARD_SHORTLIST.create(window));
     }
     
     /**
      * Create a new <code>NewWizardDropDownAction</code>.
      *
      * @param window the window in which this action appears
      * @param showDlgAction the action to delegate to when this action is run directly,
      * rather than being dropped down
      * @param newWizardMenu the contribution item that adds the contents to the drop-down menu
      */
     public NewWizardDropDownAction(IWorkbenchWindow window,
             ActionFactory.IWorkbenchAction showDlgAction,
             IContributionItem newWizardMenu) {
         super(WorkbenchMessages.NewWizardDropDown_text);
         if (window == null) {
             throw new IllegalArgumentException ();
         }
         this.workbenchWindow = window;
         this.showDlgAction = showDlgAction;
         this.newWizardMenu = newWizardMenu;
         tracker = new PerspectiveTracker(window, this);
         
         setToolTipText(showDlgAction.getToolTipText());

         ISharedImages sharedImages = window.getWorkbench()
                 .getSharedImages();
         setImageDescriptor(sharedImages
                 .getImageDescriptor(ISharedImages.IMG_TOOL_NEW_WIZARD));
         setDisabledImageDescriptor(sharedImages
                 .getImageDescriptor(ISharedImages.IMG_TOOL_NEW_WIZARD_DISABLED));

         setMenuCreator(menuCreator);
     }

     
     /* (non-Javadoc)
      * @see org.eclipse.ui.actions.ActionFactory.IWorkbenchAction#dispose()
      */
     public void dispose() {
         if (workbenchWindow == null) {
             // action has already been disposed
 return;
         }
         tracker.dispose();
         showDlgAction.dispose();
         newWizardMenu.dispose();
         menuCreator.dispose();
         workbenchWindow = null;
     }

     /**
      * Runs the action, which opens the New wizard dialog.
      */
     public void run() {
         if (workbenchWindow == null) {
             // action has been disposed
 return;
         }
         showDlgAction.run();
     }

 }

